Both character's have all of their henchmen that they've ever had at any point in their history at their disposal (Desaad, Kalibak, Female Furies, etc for Darkseid; Mister Sinister, War Hulk, Archangel, Wolverine as Death, etc for Apocalypse) in an all out war, including alternate realities/timelines (AoA, etc).
[To even the playing field, Darkseid can not use his Omega Effect to simply disintegrate everyone.]
Who would win, and who would be the last character(s) standing?
This is really really hard to know in all truth i think both armies might destory each other and only Apocalypse since he is immortal would servive and if he did perish he would just posses Darkseid and live on maybe i sounding stupid im just saying what i think at the moment.
Not entirely sure of the backstory on Stryfe, but he was not under Apoc's control. In Pockie's defense, he was VERY weak at the time, and in a rematch would give Stryfe a run for his money.
Actually, there was a storyline where Apocalypse kidnapped and raised the Cable clone (Stryfe) thinking it was Cable, the mutant destined to kill him, so Stryfe would count.
Apoc's historical henchman would be (off the top of my head):
Archangel
Ship (Sentient Cellestial Ship)
War (Original)
Pestilence
Famine
Wolverine as Death
Hulk as War
Holocaust
Caliban
Deathbird
The Skrulls
Ahab
The Hellhounds
Mr. Sinister*
Exodus
Stryfe
AoA Mutants
darkseid has been laying siege to mofo'kers for countless millenia. apoc just had a few thusand years at this. forget warhulk and all them remember that the henchmen of apokolips are gods, excpet for the parademons of course. an entire army vs marvel erathlings no way they even get to say KEM! it would be over b4 then
well, since "alternate realities/timelines" are allowed, then this means 'Seid gets the use of the Kal-El who was raised on Apokalips (from Superman: The Dark Side), pre-C Validus, and pre-C clones of Superman, Orion, Kalibak & an Oan.